Pressure regulator



NOV. 1,1932. 1:, B, STQVER 1,885,639

PRESSURE REGULATOR Filed Jan. 14, 1930 INVENTOR 7 77am? 5. Singer ATTORNEYS Patented Nov. 1, 1932 UNITED STATES PATENT OFFICE FRANK B. STOVER, OF DETROIT, MICHIGAN, ASSIGNOR T0 SKY SIPECIALTIES CORPORA- TION, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN PRESSURE REGULATOR Application filed January 14, 1930. Serial No. 420,739.

The present invention pertains to a novel pressure regulator designed particularly for use in connection with a pressure fluid tank. More specifically, the device is intended to be used on a compressed air tank carried by an aeroplane for operating the engine starter.

The principal object of the invention is to provide an elficient device of this character which will form a bypass to the atmosphere when a predetermined pressure in the tank is reached. Preferably, the charging pump is in communication with the exhaust but normally obstructed therefrom by a valve which opens on the attainment of a given maximum pressure and closes at a given minimum pressure in the tank. 1

A further object of the invention is to provide an abrupt or sudden action of this valve as distinguished from a fluttering action which might occur during small pressure variationsfrom the critical pressure. This object is accom lished by means of a snap action device w ich permits the valve to open on the attainment of the predetermined maximum pressure and prevents closing of the valve until the tank pressure has fallen considerably from this maximum.

It is desirable, however, to reduce or eliminate as far as possible the range between the valve-opening and valve-closing pressures, but at the same time to maintain the abrupt action of the valve. Another object of the invention is to bring about such a condition and is accomplished by balancing the pressure-sensitive member each time pressure fluid is withdrawn from the tank, as a consequence of which the snap action operates to open the tank to the compressor if the tank pressure is at all below maximum.

The invention is fully disclosed by way of example in the following description and in the accompanying drawing, in which Figure 1 is a longitudinal section of the device;

Fig. 2 is a section on the line 22 of Figure 1;

Fig. 3 is a detail elevation of the snap action member; and

Fig. 4 is a cross section thereof;

Reference to these views will now be made by use of like characters which are employed to designate out.

The device includes a body 1 which is formed with chambers, passages and ports for the desired flow of fluid, in a manner which will presently be described. The device is mounted in one of the walls of a receptacle 2 for compressed air or other fluid under pressure, and the attachment is made by means of a tapped ring 3 fitted into a wall of the container and having the lower end of the body member 1 fitted therein.

The body further includes a cap 4 threaded on the member 1 and formed with a chamber 5 partitioned by means of a screen or strainer 6 held in osition by a spring ring 7. Into the top oi the cap is threaded a nipple 8 which establishes connection between a pressure supply line from a pump (not shown) to the chamber 5 at the upper or outer side of the strainer 6.

Through the member 1 is formed a fluid intake passage 9 extending from the chamber 5 to the tank. The lower portion of the passage is restricted at 10 and then enlarged at 11 to form a valve seat 12. The enlarged lower end 11 contains a ball valve 13 normally in open position and held against dropping into the receptacle by a pin 14 which bridges theportion 11.

In the chamber 9 and above the restriction 10 is mounted a spring 15 on which in turn is mounted a plunger 16 containing a composition filler 17. In the upper end of the passage 9 is threaded a valve seat member 18 having a passage 19 therethrough in order not to obstruct the flow of fluid from the chamber 5 to the tank 2. The filler 17 normally seats against the member 18 and is of such composition as to form an eflicient seal at this point. The member 16, 17 thus functions' as a valve held closed against the passage 19 by the spring 15, but is removed from the member 18 by pump pressure in the intake line. In the event that the cap 4 is removed, escape of fluid from the tank is prevented by the seating of the valve 17 against the seat 18, thereby preventing recorresponding parts through ill) turn of pressure from the tank 2 to the compressor.

Into the ring 3 andadJacent the passage 9 is fitted an elongated barrel extendmg into the receptacle 2. The upper end of the barrel is tapped at 21, and the body member 1s also tapped at 22 in continuation of the 1 nternal threads 21. This arrangement permits the insertion of a threaded ring or nut 23 into the barrel for a purpose which will presently appear. This member however is not'inserted until other essential parts have been assembled, the order of'assembly beingapparent from Figure -1 and} not necessarily following the order of description.

The barrel 20 contains a plunger 24 having at its lower end a disk25 resting on an internal shoulder 26 formed at the lower end of the barrel. A plug 27 is slidably mounted in the barrel andengages the lower surface of the disk 25. The lower extremity of the barrel is enlarged at 28 and tapped at 29 to receive a diaphragm .30 protected by a th1n brass washer 31 finally clampedi'nto the lower end of the barrel by a screw 32 threaded into the tapped hole 29-and bearing against the washer 31 which prevents distortion of the diaphragm by the turning and tightening of the screw. The plunger 24 is surrounded by a compressed spring 33 resting on the disk 25and bearing against the member 2. It will now be apparent that the resistance presented by the diaphragm to the pressure within the receptacle 2 is governed by the spring,

33 which in turn is regulated by adjustment of the nut 23.

Into the upper end of the tapped hole 22 of the body member 24 is screwed a plug 34 having aflreduced lower end 35 extending downwardly into the barrel. The member 34, 35 is formed with a longitudinal bore 36 into which is slidably received a stem 37 extending upwardly from the plunger 24. A snap action member consisting of apiece of tubing 38 has its upper end threaded on the upper endof the reduced portion 35. The tubing has a plurality of longitudinal slots 39 extending from its lower end a considerable distance upward to form a plurality of spring fingers 40. The lower extremities of the fingers are formed with inwardly extending points or prongs 41 which constitute a seat for a head-42 on the stem 37. The operation of this snap action device will presently be described.

The upper end of the bore 36 is enlarged and tapped at 43 to receive a nipple 44 formed with an intermediate valve seat 45. The nipple 44 is in turn surrounded by a tapped bushing 46 threaded thereon and fitted into. the plug 34. Within the nipple 44 is mounted a ball valve '47 normally resting on the seat 45 by its own weight. In the upper end of the bushing 46 is threaded a ring 48 which permits communication between the chamber 5 and the nipple 44 and also prevents expulsion of the valve 47 from the nipple.

The upper portion of the stem 37 is further reduced at 50 and extends upwardly into the nipple 44 to a point normally below the valve 47. The longitudinal bore 36 is of larger diameter than the stem 50 at a point 51 below the nipple, from which point is formed a duct 52 extending radially to a peripheral groove 53 in the plug 34. An exhaust pipe 54 is fitted into a side of the body member 1 and connected with the groove 53 by a duct 55 in the member 4.

An outlet pipe 56 extends from the tank 2 to the device to be operated by the pressure fluid, such as a starter for an internal combustion engine. In this pipe is inserted a control valve 57 operated when desired by any suitable means. A branch 58 from the pipe 56 is connected into the body member 1 and brought into communication with the tapped hole 22 and the interior of the barrel through a duct 59 in the member 1, whereby the tank pressure is applied to the upper surface of the diaphragm 30 each time the valve 57 is opened-L This pressure balances the diaphragm 30 against the tank pressure on the lower side thereof, and the pressure differential exerted by the spring 33 is suflicient to move the head 42 downwardly past the prongs 41, in the event that the head should be above the prongs, and thus operate the snap action and permit the tank to be charged by the compressor, as will appear more fully below. This action is instantaneous on opening the valve 57, but the pressure fluid conveyed to the barrel 20 is soon reduced to atmospheric pressure through the line 58 and the Iengine cylinders in communication therewit Assuming that the ressure on the upper side of the diaphragm 1s atmospheric but that the pressurewithin the tank is gradually increasing to an excessive point, such accumulation will continue until the pressure within the tank is suflicient to overcome the tension of the spring 33 plus the atmospheric pressure within the barrel 20, when the plunger 24 will be raised and the valve 47 thrown oif its seat by the stem 51, so that the compressed fluid entering from the pump through the nipple 8 will be bypassed through the nipple 44, ducts 52 and 53 to the exhaust pipe 54.

It is desired however that the plunger 24 move abruptly in either direction to hold the valve 47 open for a considerable period of time, in preference to a sensitive response of the plunger to small pressure changes in the tank 2 and consequent fluttering of the valve 47 which would tend to cause a constant leak. The snap action device is provided for the purpose of causing the plunger and valve 47 to act abruptly, even though there may be a considerable differencebetyveen the pressures maximum.

at which the plunger will rise and descend. The plunger cannot rise to valve-opening position until the head 42 passes the prongs 41 by bending the fingers 39 to a bow formation. The plunger will therefore rise only when there is sufficient pressure beneath the diaphragm to pass the head 42 beyond the prongs 41 in the manner described, to open the valve 48 abruptly as distinguished from a gradual opening if the spring 33 were the only resistance.

The reverse or closing movement of the plunger is also abrupt, occurring only'when the pressure of the spring 33 exceeds the tank pressure to an. extent to force the head 42 The communication of tank pressures to thebarrel 20 on opening the valve 57, how ever throws the snap action even though the tank pressure has dropped only slightly below the In other words, if the valve'47 is open prior to operating the engine starter, it will be closed and the tank 2 will be permitted to be charged from the compressor each time the starter is operated, thereby restoring the tank pressure lost in operating the starter, however small the loss may be.

A duct extends from the" passage 9 and communicates with a line 61 connected into the body 1 and leading to a pressure gauge. The pressure in the tank tends to move the valve 13 against its seat 12. but the leakage around the valve is suflicient evidently to establish the full tank pressure in the line 61 and the pressure gauge and hence to balance the valve 13 so that it rests on the pin 14. If the pressure gauge or the line 61 should be disconnected for repair or replacement in such a manner as to relieve the pressure therein, the tank pressure will lift the valve 13 to its seat and thus prevent a rapid loss of tank pressure.

As a further matter of construction, the barrel 20 is held against turning by a pair of pins 62 inserted from the-peripheral wall of the member 3 and entering diametrically opposed slots 63 in the upper end of the member 20. The pins are fixed in position by solder 64 applied to the exposed ends thereof.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention, as indicated by the appended claims.

7 What I claim is:

1. A pressure regulating device adapted for connection between a pump and a receptacle comprising a body member having) a channel for establishing communication etween the pump and receptacleand having an exhaust passage adapted to communicate with the pump, a valve seat formed in said passage, a valve in said passage normally obstructing the passage at said seat, a barrel extending from said body, a diaphragm mounted in said barrel and exposed at one side to pressure within the receptacle, a

plunger operative on the diaphragm on the' other side thereof, a spring acting on said diaphragm at said other side, a stem extending from said plunger and adapted to move said valve from its seat when the plunger is moved by pressure in the receptacle, and a valved outlet pipe extending from said receptacle and connected to said barrel at the side of the diaphragm subjected to pressure of said spring.

2. A pressure regulating device adapted for connection between a pump and a receptacle comprising a body member having a channel forv establishing communication between the pump and receptacle and having an exhaust passage adapted to communicate with the pump, a valve seat formed in said passage, a valve in said passage normally obstructing the passage at said seat, a barrel extending from said body, a diaphragm mounted in said barrel and exposed at one side to pressure within the receptacle, a' plunger operative on the diaphragm on the other side thereof, a spring acting on said diaphragmat said other side, a stem extending from said plunger and adapted to move said valve from its seat when the plunger is moved by pressure in the receptacle, a snap action device operating on said plunger, and a valved outlet pipe extending from said receptacle and connected to said barrel at the side of'the diaphragm subjected to pressure of said" spring.

In testimony whereof I afiix my signature.

FRANK B. STOVER. 

